Part of the preparation for an operation is the transfer of the patient from a trolley to the table and the placement of the patient in a suitable position for the surgeon. Whatever the body position of the patient for the surgery that is vertical, dorsal or lateral, the patient must be moved to the dorsal supine position if there is cardiac or pulmonary arrest. This change must occur as quickly as possible. Heavy patients require considerable effort to rearrange in this way. The sites of the support pads used to maintain the operating position must be changed also and if they are taken away to permit unimpeded resuscitation the patient sometimes falls off the table. Back injury is accordingly a hazard for theatre staff and slow adjustability of support pads is a hazard for patients.
Earlier proposals have suggested superstructure for the table beneath which the patient is arranged or brackets which are adjustable toward and away from the patient. In U.S. Pat. No. 6,622,324, a pair of concave pads are provided on the end of arms which extend from the side of the operating table. The arms are substantially central and place the pads on the patients hips. A further pair of arms extend from the head end of the table and the pads of these arms contact the patients shoulders so that during operations wherein the table tilts to bring the patients head lower than the patients feet to give the surgeon a view of the nose or throat, the supports are designed for this position. The supports are not part of a system which is capable of adjustment to help the surgeon arrange the torso and limbs of a patient for the variety of positions needed to give surgical access.
The patient support device which is known most widely in operating theatres is the Moore device shown in the accompanying drawings marked Prior Art. The device has a saddle mounted on the table rail which supports a fixed upright post from which an arm extends horizontally across the table mattress upon which the patient lies. The arm has a slide mount which supports an upright plate with a pad for contacting the patients body. A pinch screw locks the slide in the desired site. The pads lie inboard of the table edge and if the patient's body is wider than the table, effective placement is impossible, that is with a pair of pads lying mutually opposite with the patients body therebetween, without lifting the patient clear of the arm in order to remove the arm and reverse it.
If the patient is in the lateral position for the operation, the devices are useful but if the patient should arrest, the Moore device is difficult to adjust. The mass of the patient presses the arm into the mattress. If the pinch screw can be found beneath the drapes, the pad is difficult to retract because the patients mass presses the slide into the mattress. A member of the surgical team must raise the patient to release the arm so that the pad can be moved to the edge of the table allowing the patient to be rolled facing upwards in the supine position. One or more team members must lean over the patient and try to lift the torso and it is during these episodes, or even routine changes requested by the surgeon, that back injuries to the team have occurred. Arrests are sudden and the team must move the patient quickly to the resuscitation position.
Some surgical procedures evolve energetic manipulation of the patients limbs. Joints receiving a metal prosthesis must withstand mallet blows. The pinch screw may loosen during such vigorous movement and allow the patient to move. The pad cannot be raised or angled to suit the body shape of the patient. The pad cannot be quickly adjusted to lie beyond the width of the operating table.
An equally serious drawback is lack of height adjustment. Despite large variation in body sizes, only two standard height pads are provided to all theatres. It is common for the pad to stand too high and to thereby impede the surgeon's access. This is especially so with operations on the shoulder.
Patients must lie on the steel arm for the duration of the operation and suffer needless bruising.
The pinch screw is small and cannot easily be located when covered by surgical drapes. If the surgical team member lifts the drapes to find it or the clamp loosens spontaneously and falls to the floor, the drapes too may slide off. The operation must then be interrupted while replacement sterile drapes are brought and applied. This is an unwelcome expense in theatre work.